KR20130122940A - Planning system for neurostimulation therapy - Google Patents

Abstract

A system is provided for planning the implantation of neurostimulatory probes. The system receives an input for receiving anatomical data comprising information about the position and orientation of at least one fiber bundle in a target area, and receiving therapeutic information including information about the stimulus preference of the at least one fiber bundle. Based on the input, the position, direction and stimulation preference of the at least one fiber bundle, the probe at substantially optimal position and orientation is substantially parallel and / or low stimulation preference to at least one fiber bundle with high stimulation preference. An optimization module for calculating at least one optimal position and at least one optimal direction for implantation of a neurostimulatory probe capable of generating an electric field gradient substantially perpendicular to at least one fiber bundle having An output for providing position and orientation.

Description

Planning system for neurostimulation therapy {PLANNING SYSTEM FOR NEUROSTIMULATION THERAPY}

The present invention relates to a system for planning implantation of neurostimulatory probes, comprising: an input for receiving anatomical data comprising information about the location of at least one fiber bundle in a target area, the stimulation preference of at least one fiber bundle Based on the input for receiving therapeutic information including information on preferability, the location of the at least one fiber bundle and the stimulation preference, the probe will stimulate the at least one fiber bundle with high stimulation preference at the optimal location. And an optimization module for calculating an optimal position for implantation of a neurostimulatory probe, and an output for providing the optimal position.

The invention also relates to a method and computer program product for planning implantation of neurostimulatory probes.

Systems for providing neurostimulation through implanted probes are used to treat diseases such as chronic pain, Parkinson's disease, tremors, and muscle dystonia. Neurostimulation is used to stimulate the nervous tissue of the brain, spinal cord and peripheral nerves. In the following, neurostimulation of brain tissue will be discussed. However, the systems and methods according to the invention can also be used, for example, for neurostimulation of the spinal cord and peripheral nerves. The probe is surgically implanted in the brain, near the brain tissue to be stimulated. When using neurostimulation, it is important to stimulate the tissues that require stimulation and to avoid stimulation of other nearby tissues. Accordingly, the correct placement of the probe is an important step in successful neurostimulation therapy. In known systems for planning implantation of probes, imaging techniques such as magnetic resonance imaging (MRI) are used to visualize the target area. The surgeon seeks to locate a structure that requires stimulation and to define a surgical plan to implant the probe into the identified structure.

In pending patent applicant application number EP10159853.0 (internal reference number PH014693EP1) of the same applicant as the present patent application, an example of a system for planning a neurosurgical operation is described. The system described in this patent application uses other imaging techniques to determine surgical trajectory that avoids critical neural structures. The system may be useful for planning trajectories for implanting neurostimulation probes, but may not be used to determine the optimal location for successful neurostimulation treatment.

A known method for stimulating the correct tissue area is to implant a probe with a plurality of electrodes and only select a subset of these electrodes to stimulate a particular tissue area. This is described, for example, in US patent application US 2008/0215125. This US application describes a probe having a plurality of electrodes implanted near the area under consideration. The charge is supplied to a subset of these electrodes to selectively stimulate specific tissue regions. Also in US Pat. No. 7,442,183, a subset of the plurality of electrodes is activated to adjust the electric field with respect to the target area. In US 7,442,183 it is noted that selective activation of a subset of electrodes forms the correct probe position for less important target structures.

While the use of electrode arrays can adjust the 3D electric field distribution for specific tissue regions, the full range of 3D stimulation patterns that can be generated is still dependent on the exact position and orientation of the probe. For optimal therapy delivery options and their tuning flexibility, optimal lead positioning should be arranged at the therapy planning stage.

Object of the Invention

It is an object of the present invention to provide a system for planning the implantation of neurostimulatory probes, which allows the probes to be more accurately positioned to improve neurostimulation treatment.

Summary of the Invention

According to a first aspect of the invention, this object is a system for planning implantation of a neurostimulatory probe, comprising: an input for receiving anatomical data comprising information about the position and orientation of at least one fiber bundle in a target area An input for receiving therapeutic information including information about the stimulus preference of the at least one fiber bundle, the position, orientation and stimulation preference of the at least one fiber bundle, wherein the optimal position and orientation of the probe is high At least one for implantation of neurostimulatory probes capable of generating an electric field gradient substantially parallel to at least one fiber bundle with stimulation preferences and / or substantially perpendicular to at least one fiber bundle with low stimulation preferences Optimal for calculating the optimal position and at least one optimal direction It is achieved by providing a system comprising a signification module and an output for providing an optimal position and orientation.

The planning system according to the present invention takes into account the location of the target structure as well as its orientation for planning the implantation of neurostimulatory probes. In particular, for fiber bundles, the direction of the stimulating electric field relative to the direction of the fiber bundles is an important factor in determining the effectiveness of neurostimulatory therapy. While the prior art planning system is only intended to stimulate the brain at a specific target location, the planning system according to the invention also takes into account the direction of the target fiber and the direction of the gradient of the stimulating electric field that may be generated by the neurostimulation probe. do. It is noted that the planning system according to the invention can also be used to plan the implantation of two or more probes. In the following, however, we assume that only one probe is implanted.

It has been found that activation of certain fibers is most easily achieved when the electric field gradient is parallel or approximately parallel to the targeted fiber bundle. Selective non-activation of the fiber is most easily achieved with an electric field gradient perpendicular or approximately perpendicular to the non-targeted fiber bundle. Using imaging techniques in the art, for example Diffusion Tensor Imaging (DTI), it is possible to identify individual fiber bundles, and their position and orientation. The optimization module uses this information to determine the optimal probe position and orientation. The planning system according to the invention thereby generates a stimulating electric field with a (approximately) parallel to the fiber bundle which should be stimulated and a field gradient which is (approximately) perpendicular to the fiber bundle which should not be stimulated. Makes it possible to let.

The system according to the invention may comprise an imaging device and may derive the fiber bundle position and orientation from the images obtained by the imaging device. Alternatively, the system may receive image information regarding fiber bundle position and orientation from an external source, or the fiber orientation containing brain atlas may be registered as an anatomical image such as an MRI.

The system also receives information regarding the stimulus preference of one or more fiber bundles. Stimulus preference may be provided, for example, as a simple sequence of fiber bundles that require stimulation to achieve the desired therapeutic effect. In addition, an array of fiber bundles may be provided that should not be stimulated to avoid side effects. Stimulus preference is preferably expressed as a numerical value indicating the level of desirability for the particular fiber bundle to be stimulated. Stimulus preference may be obtained by a user selecting one or more fibers that should be stimulated (or not stimulated). For example, a pointing device, such as a mouse or a joystick, can be used to highlight important fiber bundles in the displayed image of the target area. The user may be able to impart a level of stimulus preference to the highlighted fiber bundles. Alternatively, the anatomical information can include information identifying different fiber bundles, and the therapeutic information can include information about which fiber bundles are stimulated. The system can then be arranged to select a fiber bundle that needs stimulation.

The optimization module uses collector information (anatomical information with the position and orientation of the fiber bundle, and therapeutic information indicating stimulus preference) to determine the optimal position and orientation for implantation of the probe. At the optimal position and orientation of the probe, the therapeutic effect of the stimulus can be maximized, or the side effects of the stimulation therapy can be minimized. In most cases, the optimal position and orientation of the probe will provide a balance between maximizing the expected positive effect and minimizing the expected side effects. Instead of one optimal position and orientation, the optimization module may also provide a number of optimal or near optimal positions and orientations or a range of suitable positions and orientations.

If the probe to be implanted is a multi-electrode probe, the optimization module may take into account possible 3D electric field distributions that may be generated by the plurality of electrodes. Due to the constraints of the distribution of the stimulation electrodes (eg, the geometry of the probe, the limitation of the number of probes that can be safely implanted), all 3D arrangements of the stimulation field cannot be constructed. For example, for axially shaped probes with multi-cylindrical electrodes, it is easier to control the field gradient parallel to the axis of the probe than to control the vertical field gradient. Larger field arrangements are available for probes involving (2D) electrode arrays on cylindrical carrier bodies. However, due to the inevitable geometric limitations on the placement of the electrodes on the probe body, only long gradients within certain limits are still possible. The optimization module in the system according to the invention can solve this problem by comparing the possible 3D direction with respect to the stimulation field with the position and orientation of the fiber bundle which should be stimulated (or not stimulated).

At output, the planning system provides the optimal position and orientation for implantation of the probe. Such information can be provided, for example, by superimposing a graphical representation of the probe on an image of the target area.

According to a second aspect of the invention, a method of planning the implantation of a neurostimulatory probe is provided. The method includes receiving anatomical and therapeutic data, calculating at least one optimal position and at least one optimal direction for implantation of the probe, and providing an optimal position and orientation do. Anatomical data includes information regarding the location and orientation of at least one fiber bundle in the target area. The therapeutic information includes information regarding the stimulus preference of the at least one fiber bundle. The calculation of the optimal position and orientation for implantation of the probe is based on the position, orientation and stimulus preference of at least one fiber bundle in the target area. In an optimal position and orientation, the probe may generate an electric field gradient that has a high stimulus preference substantially parallel to at least one fiber bundle and / or has a vertically low stimulus preference in performance for at least one fiber bundle. .

According to another aspect of the present invention, a computer program product is provided for causing a processor to perform the method described above. These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described below.

In the drawings,
1 schematically shows a planning system according to the invention.
2 shows a flowchart of a method according to the invention.

1 schematically shows a planning system 10 according to the invention. Planning system 10 may be implemented by a suitably programmed personal computer or by a dedicated medical system. The planning system 10 includes at least an input 18 for receiving anatomical and therapeutic information, and an optimization module for calculating an optimal position and orientation for implantation of the probe. The optimization module can be executed in software, running on the processor 11. System 10 preferably includes or is coupled to a user interface for the user to control the planning process. The user interface may comprise a keyboard and / or a pointing device, for example a mouse 14 for interacting with a graphical user interface displayed on the display 13. The display 13 is also connected to the processor 11 via an output 19. The storage medium 12 is also connected to the processor 11 and may be used for storing program code, configuration data, medical information database or patient data, for example. Storage medium 12 may also include anatomical and therapeutic data needed to plan the implantation of the probe.

System 10 may include or be coupled to imaging device 15 for obtaining images of a target area. These images are the table? It can be used to determine the position and orientation of at least one fiber bundle in the area. Usually Diffuse Tensor Imaging (DTI) is used to visualize fiber bundles, but other imaging techniques may also be suitable for the planning method according to the present invention. The processor 11 may be configured to derive the position and orientation of the fiber bundle from the image. If no imaging device 15 is used, the system 10 may receive at the input 18 a list or database, for example, with position and orientation data of the fiber bundle in the target area. In the following, with reference to FIG. 2, how the system 10 is used to calculate the optimal position and orientation for implantation of a probe is described.

2 shows a flowchart of a method according to the invention. The method starts with an input step 21. System 10 receives anatomical information 30 and therapeutic information 40. The anatomical information 30 may be in the form of an image of the fiber bundle 31 in the target area or may simply be data describing the fiber bundle location and orientation. Where anatomical information 30 is provided in the form of an image, the fiber bundle position and orientation may be determined by dedicated image recognition software. Anatomical information 30 may include, for example, larger brain regions, allowing the user to select a target region. Selecting the target area may be made using the pointing device 14 to select a portion of the 2D or 3D graphical representation of the area where anatomical information 30 is available, for example.

Therapeutic information 40 includes information regarding the stimulus preference of a particular fiber bundle 31. Therapeutic information 40 may be a symptom associated with medical information or derived from a database having medical information. Alternatively, the user may be able to indicate whether the fiber bundle 31 should be stimulated and not. Stimulus preference can be a binary value representing 'stimulation' or 'non-stimulation', but can also be a continuous or discontinuous number on a scale ranging from 'highly stimulus preference' to 'absolutely non-stimulating'. have. When the anatomical data 31 and the therapeutic data 40 are combined, the combined data 50 produces a fiber bundle 31 and a list or database with position, orientation and stimulus preference for each fiber bundle. Include. It is noted that the fiber bundle 30 is not a straight line of uniform thickness. The input data preferably describes the full trajectory of the fiber bundle 30. Other portions of the fiber bundle 30 may have different directions or appearances. Stimulus preference of the fiber bundle 30 may also vary depending on the fiber bundle 30. The stimulation of the fiber bundle 30 may be dependent on the diameter of the fiber bundle 30. In FIG. 2, the combined data is visualized by highlighting the fiber bundle 32 that should be stimulated, and preferably the fiber bundle 33 that should not be stimulated. Such visualization may also be provided on the display 13 of the system 10.

In the optimization step 22, the combined data is used to calculate the optimal position and orientation for one or more probes (50). At the optimal position and orientation of the probe, the therapeutic effect of the stimulus can be maximized (probe 35 in FIG. 2) or the side effects of the stimulation therapy can be minimized (probe 34 in FIG. 2). In most cases, the optimal position and orientation of the probe will provide a balance between maximizing the expected positive effect and minimizing the expected side effects. Since the fiber bundle 31 can have different directions at different locations, the optimal probe position can be close to the section of the fiber bundle 32 to be stimulated, which section is adjacent to the fiber bundle 33 which should not be stimulated. Perpendicular to).

For optimal stimulation of the target fiber 23, the probe is placed near the bundle 32 to be stimulated. If the probe is closer to the fiber, the stimulating electric field may be less powerful and the chance of side effects caused by stimulation of nearby fiber bundles is reduced. Fiber bundles tend to be narrower at the center than near the ends. When probes are used to stimulate bundles of relatively small diameters, less powerful stimulating electric fields are required.

If the probe to be implanted is a multi-electrode probe, optimization step 22 may take into account possible 3D electric field distributions that may occur after implantation. Due to limitations on the distribution of the stimulation electrodes (eg, the geometry of the probe, limitation of the number of probes that can be safely implanted), the 3D placement of all the stimulation fields may not be constructed. Accordingly, the optimization step 22 may compare the possible 3D direction with respect to the magnetic field to the position and direction of the fiber bundle that should be stimulated (or not stimulated).

In an output step 23, the result of the optimization step 22 is provided. The optimal position and orientation can be provided, for example, as a data file with information about the optimal position and orientation. This data file can be used as input to the system for monitoring the actual implantation of the probe or probes. Instead of the planning system 10 providing an optimal location and orientation to the data file, the display 13 of the planning system 10 may display an image of the target area supplemented with a graphical representation of the probe to be implanted. In addition, the tolerance range can be expressed as to indicate how accurately the probe should be placed. Preferably, the system is also configured to indicate the actual location of the actual probe during implantation. This allows the surgeon to compare the actual position and orientation of the probe with the calculated optimal probe position. This can be realized, for example, by superimposing the calculated optimal position for the probe on a real time image of the target area.

It will be appreciated that the invention also extends to computer programs, in particular computer programs on or in carriers configured for carrying out the invention. The program may be in the form of source code, object code, intermediate code and object code, for example in some compiled form, or in any other form suitable for use in the execution of the method according to the invention. It will also be appreciated that such a program can have many different architectural designs. For example, program code for carrying out the functions of the method or system according to the invention may be subdivided into one or more subroutines. Several different ways to distribute the function among these subroutines will be apparent to those skilled in the art. Subroutines can be stored together in one executable to form a self-contained program. Such executable files may include computer executable instructions, such as processor instructions and / or interpreter instructions (eg, Java interpreter instructions). Alternatively, one or more or all of the subroutines may be stored in at least one external library file and linked to the main program statically or dynamically, for example at run time. The main program contains at least one call in at least one of the subroutines. Subroutines may also include function calls to each other. Embodiments of a computer program product include computer executable instructions corresponding to each of the processing steps of at least one of the presented methods. Such instructions may be stored in one or more files that may be subdivided into subroutines and / or linked statically or dynamically. Another embodiment of a computer program product includes computer executable instructions corresponding to each of the means of at least one of the presented systems and / or products. Such instructions may be stored in one or more files that may be subdivided into subroutines and / or linked statically or dynamically.

The carrier of the computer program may be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, for example a ROM, for example a CD ROM or a semiconductor ROM, or a magnetic recording medium, for example a floppy disk or a hard disk. In addition, the carrier may be a transmittable carrier, such as an electrical or optical signal, which may be delivered by an electrical or optical cable, or by radio or other means. When a program is implemented with such a signal, the carrier may be constituted by such a cable or other device or means. Alternatively, the carrier may be an integrated circuit with a program embedded therein, and the integrated circuit may be configured for performing related methods or for use in the execution of such methods.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention and that those skilled in the art can design several alternative embodiments without departing from the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The use of the verb “comprises” and its conjugations does not exclude the presence of elements or steps other than those described in a claim. Elements described in the singular do not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several separate elements and by a suitably programmed computer. In the device claim enumerating several means, several such means may be embodied by one and the same item of hardware. The fact that certain measures are described in different dependent claims does not specify that a combination of these measures cannot be advantageous.

Claims (7)

An input for receiving anatomical data comprising information relating to the position and orientation of one or more fiber bundles in the target area,
An input for receiving therapeutic information comprising information relating to stimulation preferenceability of one or more fiber bundles,
One or more fibers having substantially parallel and / or low stimulation preferences relative to the one or more fiber bundles where the probe at the optimal position and orientation has high stimulation preferences, based on the location, direction and stimulation preferences of the one or more fiber bundles. An optimization module for calculating one or more optimal positions and one or more optimal directions for implanting neurostimulatory probes, which can generate an electric field gradient substantially perpendicular to the bundle, and
A system for planning implantation of neurostimulatory probes, comprising an output for providing an optimal position and orientation. The system of claim 1, wherein the neurostimulatory probe comprises an array of stimulation electrodes and the optimization module takes into account the range of 3D electric field distribution that may be generated by the array of stimulation electrodes. . The neurostimulation probe of claim 1, further comprising a user interface for the user to select one or more fiber bundles having a target area and / or high stimulation preferences and / or one or more fiber bundles having low stimulation preferences. System for planning transplant. The system of claim 1, wherein the output comprises a display for displaying a graphical representation of a target area and an optimal location and orientation for implantation of the neurostimulation probe. . The system of claim 1, further comprising a magnetic resonance imaging device for acquiring anatomical data. Receiving anatomical data comprising information relating to the location and orientation of one or more fiber bundles in the target area,
Receiving therapeutic information including information relating to the stimulus preference of one or more fiber bundles,
Based on position, direction and stimulation preferences, the probe is substantially parallel to one or more fiber bundles with high stimulation preferences and / or substantially to one or more fiber bundles with low stimulation preferences Calculating one or more optimal positions and one or more optimal directions for implanting neurostimulatory probes, which can generate electric field gradients vertically, and
-Providing an optimal location and orientation, the method of planning the implantation of neurostimulatory probes. A computer program product for planning implantation of neurostimulatory probes in which a program is operated such that a processor performs the method according to claim 6.

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